264 An Essay on Dreaming, bfc. 



nambulism, therefore, can only talte place when part of the brain 

 is awake, and in communication with the nerves of locomotion. 

 These considerations, with others detailed above, will also suffice 

 to account for the fact recorded by the excellent writer so often 

 referred to, " that many soldiers, in the retreat of Sir John Moore, 

 fell asleep on the inarcii, and still continued to walk with their 

 comrades*." 



But whatever may be thought of these speculations, there is 

 no difficulty in comprehending Dr. Spurzheim's development of 

 the nature of dreaming : and if we are acquainted with the in- 

 adequate theories of his predecessors, to comprehend his expla- 

 nation is but an easy step to its unqualified adoption. It ac- 

 counts for every phaenomenon connected with the subject, hitherto 

 unexplained. If the whole brain is locked up in sleep, there is 

 no dream. If a portion of it is emancipated, thoughts peculiar 

 to that portion arise, and those thoughts are dreams. The me- 

 chanic's imagination may rove among machinery, the mathema- 

 tician may solve a problem, the orator pour forth unstudied elo- 

 quence, the poet unpremeditated verse, the wit delectable jests, 

 the musician unprecedented harmony; yet this does not always 

 occur, but occasionally. If the peculiar organ happens to be 

 asleep, there is no music, no wit, no poetry, no oratory, no ma- 

 thematics, no mechanics — a different faculty may be active, and 

 these individuals may wander through inextricable difficulties, or 

 fly before wild beasts, or combat with enraged assailants, or dis- 

 solve in a cold sweat at the frightful visit of some spectre from 

 the grave. It is not because the organ may have been frequently 

 or recently exercised, that it is emploved in a dream ; it is sim- 

 ply because it has escaped from the trammels of sleep which still 

 envelop the remainder of the brain, or at least the senses, which 

 open a communication with the external world, and supply the 

 only means by which we are informed whether similar objects of 

 thought are realities or illusions. This theory, therefore, ex- 

 plains why we sometimes have dreams and are sometimes with- 

 out them — why we sometimes dream on the subject most familiar 

 to our reflections, and sometimes ramble into the most unaccount- 

 able fancies — and lastly, why happiness and misery are occa- 

 sionally the companions of our sleep, according as peculiar or- 

 gans are gently affected or rudely agitated by the thoughts which 

 engage them — pleasure frequently losing itself in pain, as the 

 mental disturbance increases, till at length the accumulating un- 

 easiness trespasses on the sensorium, or the very organs of sense, 

 when, suddenly awaking, we find an unexpected relief from our 

 griefs, vexations, and terrors. 



[To be oontinued.3 

 * Rees's Cyc. article si-eef. 



XLIII. Prifi- 



